Propeller



" April 22 1924. 1,491,512

F. BRAcco PROPELLER Filed May 29, 1922 .2 sheets-sheet 1 A TTOH/VEYS April z2 1924. 1,491,512

F. BRACCO PROPELLER Filed May 29, 1922 2 Sheets-Sheet 2 mlm/ron FEEDER/of B/fwcco Br 6% wmf m A TTOHNEYS Patented Apr. Z2, 1924.

UNTED STATES tratan.

FREDERICK BRACCO, F RUTHERFORD, NEW JERSEY'.

rnornttnn.

Application led May 29, 1922. Serial No. 564,434.

To all whom t may concern:

Be it known that I, FREDERICK BRAoQo, a citizen of the United States, and resident of Rutherford, county of Bergen, and State v of New Jersey, have invented certain new and useful Improvements in Propellers, of which the. following is a specification.

My invention relates to Propellers and has for its object to provide a novel and simple construction and arrangement in which the propeller is capable of being readily folded to an inoperative position when its services are not required. Other more specic objects of the invention will appear from the description hereinafter and the features of novelty will be pointed out in the appended claims.

In the accompanying drawings, which show several examples of the invention without defining its limits, Fig. 1 is a sectional elevation of one form of construction showing the propeller in its operative position; Fig. 2 is a similar view illustrating the propeller in its folded inoperative position; Fig. 3 is a plan view showing the parts in intermediate positions; Fig. 11 is a` sectional view on the line 4-4 of Fig. 1; Fig. 5 is a similar view on the line 5-5 of Fig. 2; and Fig. 6 is a diagrammatic view illustrating the actuating mechanism. As shown in Figs. 1 to 6 inclusive, the construction comprises a casing 15 supported upon the stern 16 of the ship or vessel at a suitable point and extending inwardly in coincidence with the axis of rotation of the propeller. The outer end of said casing 15 is closed by means of a cover 17 pivoted at 18 and movable to and from its closed position in any convenient manner as by means of a mechanically operated shaft 19; in its closed position the cover 17 fits into a con venient groove 20, as shown in Fig. 2, whereby the casing 15 is sealed to prevent the admission of water thereto. The inner end of e5 the casing 15 is closed by means of a head 21 which provides a bearing for the hollow or tubular shaft 22; the latter, at its outer end carries a continuing closed shell 23 upon which the propeller blades 211 of any cono ventional type and number, are pivoted at 25. The blades 24 areformedwith toothed' segments 26 arranged in mesh with annular teeth 27 formed on an auxiliary shaft 28 journalled at one end in a block 29 fixed within the shell 23 and at itsother end in a sleeve 30 fitted Within the inner end' of said hollow shaft 22 as illustrated in Fig..2; the auxiliary shaft 28 furthermore, through the medium of a screwthread 27', is in screwthreaded engagement with a block 29a`secured within the hollow shaft 22 in any conventional manner, which block 29a, in addi-` tion to its other functions, serves yalso to add rigidity to the construction and to provide an additional bearingfor the auxiliary shaft 28. A gear 31 is rigidly connected with the tubular shaft 22, for instance as indicated in Fig. 2, and serves as a means for transmitting operative motion to the propeller as will appear more fully hereinafter. The previously mentioned sleeve 30, which is also located at the inner end of the shaft 22, further extends into a hollow box-gear 32, the teeth of which are preferably inclined across the axis of rotation and which is secured upon the auxiliary shaft 28 in any wellknown way as by means of a pin 33. For the purpose of preventing the box-gear 32 from being completely withdrawn from the sleeve 30, the latter is provided with an annular flange 34, which itself is formed with a notch 35 arranged to cooperate with a lug 36 on the gear 32 to couple it tothe sleeve 30 and consequently to the hollow shaft 22; the box-gear 32 is further provided with a second lug 37 adapted to enter a notch 38 formed onthe gear 31 to directly couple the shaft and box-gear together in the operative position of the propeller as will appear more fully hereinafter. It will be understood that the notches 35 and 38 and the lugs 36 and 37 are so shaped as to readily move into and outv of engagement with each other and serve to l lock the blades 24 in their respective positions.

For the purpose of adjusting the propeller'l blades 24: to and from an operative position, the casing 15 is constructed in the form of a cylinder in which a piston 39 is-reciprocable, said piston being carried by the 'l'cl- 100 low shaft 22 in a manner to permit free rotation thereof but to compel said shaft 22 to partake of the reciprocating movements of said piston. Any suitable mechanism may be provided for operating the piston 39 in the intended manner; for instance as shown in the drawings screw-threaded rods 40 are rigidly connected with said piston 39 and extend loosely through and beyond the head 21 into the interior of the ship or other vessel. The rods 40 pass through sleeves 41 with which they are in screw-threaded engagement, said sleeves being mounted in bearings 42 so as to be freely rotatable therein without being capable of longitudinal movement relatively to said bearings 42; the sleeves 41 carry pinions 43 and gears 44, the teeth of the latter being inclined across the axes of rotation for cooperation with the teeth of the box-gear 32. The pinions 43 are in mesh with intermediate gears 45 which in turn are operatively engaged with a main gear 46 mounted upon a power shaft 47 driven in any conventional and wellknown manner; suitable bearings 48 and 49,

preferably combined with the bearings 42 and suitably fixed in position, are provided for the various shafts as shown by way of example in Fig. 3. The construction further includes a gear 50 adapted to mesh with the gear 31 to operate the propeller as will appear more full7 hereinafter, said gear 50 being mounted upon a power shaft 51 which carries also a pinion 52 arranged for operative connection with a motor or other source of power. The pinion 52 is loosely mounted upon the shaft 51 and may be coupled thereto, at will, by means of a clutch 53 of any conventional type.

1n the operative position of the parts the blades 24 occupy the position illustrated in Figs. 1 and 4 in which they are locked by the engagement of the lug 37 with the notch 38; in this condition the propeller operates in the conventional manner to propel the ship or other vessel either forward or backward as occasion may require, the gear 50, whereby motion is transmitted to the gear 31 being operatively coupled to the motor or other source of power through the medium of the pinion 52 and clutch 53.

lhen the use of the propeller is not desired it may be folded into the casing 15 in the following manner: power is applied to actuate the gear 46 which in turn operates the intermediate gears 45 and the pinions 43. This brings about a rotation of the sleeves 41 which, because of their screwthreaded engagement with the rods 40 is translated into a mechanical pull whereby said rods are caused to travel linearly to, the right in Fig. 1. By this means the piston 39 is similarly moved in the casing 15 and carries with it the hollow shaft 22 and its associated elements. The lengthwise Legnaia movement of said shaft 22 toward the right in Fig. 1- nally brings the box-gear 32 into mesh with the gears 44 which partake of the rotative movements of the sleeves 41; the engagement of the gears 44 with the gear 32 is facilitated by reason of the inclination of the teeth of said gears and is accomplished with minimum of effort and friction. As soon as this engagement of the gears 44 and the box-gear 32 takes place, the latter will be set in motion and accordingly will rotate the auxiliary shaft 28 within the hollow shaft 22; by reason of the screw-threaded engagement of the shaft 23 with the block 29, said shaft as it rotates, will be shifted toward the right in Fig. 1 thus withdrawing the lug 37 from the notch 38, these two elements being shaped and dimensioned so as to make this readily possible as shown by dotted lines in Fig. 2. it the same time the teeth 27 of the shaft 28 will act upon the segments 26 and will pivotally swing the blades 24 from the operative, unfolded position of Fig. 1, through the intermediate position illustrated in Fig. 3 to the inoperative, folded position shown in Fig. 2. This folding of the blades 24 comprises a gradual and uniform movement and takes place while the piston 39 and shaft 22 are being shifted to the right in Fig. 1 through the medium of the rods 40 and sleeves 41, so that said blades are gradually drawn into the casing 15 and are fully within the same by the time the completely folded position has been reached. The described operations are continued until the lug 36 enters the notch 35 of the flange 34 thus locking the two shafts, blades, etc., in folded position, whereupon the actuation of the gears 46 and 45 is discontinued; the cover 17 is then shifted to its closed position after which the water contained in the casing 15 may be pumped or otherwise removed therefrom if desired. 1t will be understood that the lit between the piston 39 and casing 15 is fluid tight whereby water is prevented from passing beyond said piston into the vessel.

When it is desired to unfold the propeller, the reverse operation is performed; that is to say, after the cover 17 has been adjusted to its open position, the pinions 41 are actuated through the medium of the gears 45 and 46 to rotate the sleeves 41 in a direction to exert a pushing force upon the rods 40. lThis push is transmitted to the piston 39- and moves the same outwardly toward the left from the position shown in Fig. 2, through the intermediate position illustrated in Fig. 3 until the final operative position shown in Fig. 1 is reached. This movement of the piston toward the left carries with it the shaft 22 and the elements combined therewith and finally brings the box-gear 32 into engagement llO ifi-91,512

with the gear 44; as soon as this happens the box-gearv 32 will be rotated and similarly rotatey the auxiliary shaft 28 relatively to the hollow shaft 22 in a direction to cause the screw-threads 27 to shift the shaft 28 to the left in Fig. l and at the same time to cause the teeth 27 to act on the segments 26 in a manner to pivotally swing the blades 24 to the operative, unfolded position shown in Fig. 1. It will be understood that the described operations continue until the lug 37 enters the notch 38; the described shifting of the parts also brings the gear 31 into mesh with the gear to connect the propeller with its source of power. The clutch 53 being in its inoperative position during this stage, the gear 50 is free to rotate by the action of the gear 31 as the elements are adjusted to their final position, in which the gears 44 lie beyond and out of engagement with the box-gear 32. The described unfolding of the blades 24 takes place while the piston 39 and shaft 22 are being shifted to the left by the action of the rods 40 and sleeves 4l so that the blades 24 are gradually moved out of the casing l5 and are fully removed therefrom by the time the unfolding operation is completed. It will be understood that the parts are so proportioned and arranged with re-A` spect to each other that the operations of folding and unfolding the blades 24 are carried out without interference with the casing 15 or any other` part of the construction.

The invention in all of its forms is simple in construction and ecient in operation and provides an arrangement whereby the propeller blades may be easily adjusted from an operative to an inoperative position and vice versa in a minimum of time and with comparatively little eort. The invention is particularly adapted for use in vessels provided with both sail and power and permits the propeller to be quickly folded when the ship is operating under sail thus eliminating drag and other objectionable features tending to interfere with the progress of the vessel. The illustrated and described propeller arrangement may be also utilized in connection with aeroplanes and airships and anywhere else where a folding propeller is desirable.

The principal purpose of the invention is to provide a propeller construction in which the propellers are capable of convenient and practical adjustment in a manner to make them dependable for intermittent periods of service and soas to have their bulk so reduced or removed whennot in use, as to reduce or eliminate the drag without requiring a complete dismantling of the propeller and its associated parts. It will be understood that the illustrated example is intended to exemplify the invention without arbitrarily restricting the elements thereof er the construction and operation of the same. y

It may be stated that the invention is especially useful in that it provides a novel and ecient means whereby close maneuvering is possible, at will either with sail or power alone or with both sail and power. This introduces into ships drills a new element and with it a new Set of tactics which will assist materially in veering and navigating in close quarters and prove of great usefulness in also imparting to ships or vessels, for intermittent stretches under proper conditions the advantage of propulsion by a combination of sail and power. All of the above will further result in increased speed of travel, with an increased average speed thus reducing the time of travel from port to port, providing a greater control of the factors of navigation and a maximum operative economy.

Various changes in the specific forms shown `and described may be made within the scope of the claims without departing from the spirit of my invention.

I claim:

l. The combination of a casing, a shaft, propeller blades foldably carried therebyha piston slidably fitted within said casing in a water tight manner, said Apiston being connected with said shaft, means for reciprocating said piston within said casing whereby said blades are folded into the same and unfolded exteriorly thereof and a movable cover for sealing Said casin against the entrance of water when the folded blades are enclosed thereby.

2. The combination of a casing, a shaft, propeller blades foldably carried thereby, a piston slidably fitted within said vcasing in a water tight manner, said piston being connected with said shaft and means for reciprocating said piston within said casing whereby said blades are folded into the same and unfolded exteriorly of said casing.

3. The combination of a casing, a piston movable therein and having a sliding watertight connection therewith, a hollow shaft connected with said piston, propeller blades pivoted upon said shaft, an auxiliary shaft within said hollow shaft operatively connected with said blades, and means whereby said piston is actuated to shift said hollow shaft and to adjust said auxiliary shaft relatively thereto for folding said blades into said casing and for unfolding the same exteriorly thereof.

4. The combination of a casing, a piston movable therein, a hollow shaft connected with said piston, propeller blades pivoted upon said shaft, an auxiliary shaft within said hollow shaft operatively connected with said blades, a box-gear fixed upon said auxiliary shaft, screw-threaded rods rigidly connected with said piston, gearing cooperating with said rods to reciprocate Said piscon te shift said shafts and adjust the blades into and out of said casing and arranged to Operate seid box-gear to independently shift said auxiliai'y shaft to fold said blades into said casing; and to unfold the same exte- 'iorly lnereof, means for locking said blades Leeuw in eithei` position and mechanism for operating the propeller When the' blades occupy an unfolded position.

In testimony whereof l have signed this specification.

l FREDERICK BRACC@ 

